Opposition protesters last night proclaimed the beginning of a revolution in
the former Soviet republic of Kyrgyzstan after thousands fought running
battles with police in the streets.

Activists seized the parliament building and laid siege to the government headquarters. The deputy prime minister was taken hostage and there were reports from police that the interior minister had been killed. The main state television station was overrun and by early afternoon the president had declared a state of emergency.

Reports suggested about 100 people were killed and hundreds more wounded, although the death toll was expected to rise with witnesses describing piles of dead bodies in the streets.

Last night a Kyrgyz opposition leader announced on state radio that Daniyar Usenov, the prime minister, had signed a letter of resignation. It was also announced that a provisional government had been formed with a former foreign minister, Roza Otunbayeva, at its head.

President Kurmanbek Bakiyev, who reportedly fled the capital, Bishkek, is yet to resign formally.

“Power is now in the hands of the people’s government,” Ms Otunbayeva said in an address on state radio.

“Responsible people have been appointed and are already working to normalise the situation.”

Later Ms Otunbayeva, 59, who was an instrumental figure in the revolution that brought Mr Bakiyev to power five years ago, said that she planned to run an interim government for six months in order to draft a new constitution for the state.

"We have a caretaker government now in place, and I am the head of it," Otunbayeva told Reuters by telephone.

"It will remain in place for half a year, during which we will draft the constitution and create conditions for free and fair (presidential) elections," she said.

Spokesmen for the government and the president were not available for comment.

The United States, which uses an airbase at Manas in Kyrgyzstan to supply troops in Afghanistan, called for calm, saying it was “deeply concerned” by events.

An embassy spokesman in Bishkek urged all parties to “show respect for the rule of law”. The US State Department later said it had no information that the government had fallen and for the moment they believed Mr Bakiyev was still in power. Last night a US military official said flights had been suspended from the airbase amid the riots.

Earlier, Russian television stations released film showing riot police in Bishkek fleeing a screaming mob, protesters shooting at police with AK-47 assault rifles and officers being clubbed with what looked like baseball bats as they lie on the ground. Witnesses said police defending key government buildings in Bishkek had at first tried to keep a 5,000-strong crowd at bay using tear gas, stun grenades and rubber bullets.

But later, as they struggled to cope, they fired live rounds into the crowd, killing an unknown number of protesters.

There were reports of protesters seizing automatic rifles, armoured vehicles and police cars. Another 10,000 protesters stormed police headquarters in the western town of Talas.

Shamil Murat, an opposition activist, said that Moldomusa Kongatiyev, the interior minister, was beaten to death by a mob in Talas. However, the ministry denied reports of his death.

Mr Bakiyev gained power five years ago on a wave of similar protests known as the “Tulip Revolution”. Opponents say he has become as bad if not worse than Askar Akayev, the man he toppled.

Russia, which also has an airbase in Kyrgyzstan, appealed for restraint.

Ban Ki-moon, the United Nations secretary-general, who visited Kyrgyzstan this week, made an urgent appeal “for dialogue and calm to avoid further bloodshed”.

Analysts say Washington sees Kyrgyzstan as an important bulwark against radical Islam in central Asia and that the US, Russia and China will want a quick end to the anarchy.

“Russia and the United States have been competing for influence for a long time and have airbases just a few miles apart, so it is an active centre of the Great Game right now between the powers of Russia, China and the US,” said Chris Weafer, the chief strategist at Uralsib bank in Moscow.

He said living standards in Kyrgyzstan, where many families depended on money sent back from relatives working in Russia, had fallen sharply because of the economic crisis and that had probably triggered the unrest.